At present, the image of the liquid crystal display device are displayed by progressive scanning, that is, the gate lines of the display device are sequentially turned on according to the scanning information, the capacitance of each row of pixels is charged through the data lines. When the voltage of the charging is different, the gray scale present by the pixel is different, and when the pixel unit of the current row is charged, the pixel unit of the other row keeps the charged potential through the storage capacitor, after all the rows are charged to display one frame of complete image. Wherein, the charge and discharge of the data line will produce power consumption, the power consumption P=½CFV2 (C is for the capacitance, F is for the voltage switching frequency, V is for the voltage), especially when the image by the display device is an overload image, the voltage switching frequency F is larger, so that the display device has a large power consumption, when serious, the driving chip may be damaged due to high temperature.